After graduatingfrom dental school two years ago. Dr. Helen Martin purchased the dental practice of a long-time dentist who was retiring. In January of this year. she had to replace the outdated autoclave equipment she inherited from the previous dentist. Now. as she is preparing her budget for next year, she is concerned about understanding how her cost for sterilizing her dental instruments has changed. She has gathered the fol lowing information from her records: Month Number of instruments used Total autoclave cost January 850 $7,965 February 750 7.300 March 920 8.471 April 950 8.930 May 1,150 9.860 June 900 8.398 July 1,050 9.695 August 975 8.896 (a) Identify the high and low points. Activity Level 35 High point $ Low point $ Using the high-low method, what is the variable cost of sterilizing an instrument using the new equipment? {Round answer to 2 decimal places, as. 52.75.) Variable cost per instrument